Planet with no sun : free-floating in space. Astronomers have discovered a very unusual planet roaming freely through the galaxy. The planet is about 80 light years from Earth and is believed to be about six times more massive than Jupiter. The interesting thing about this planet is that it’s floating freely in space with no parent star.
This isn’t the first time an orphan planet with no sun has been discovered, but this is the first time that astronomers and scientists are absolutely sure it’s a planet. In the past, the astronomers were unable to determine if these free-floating objects were failed stars known as “brown dwarfs” or “orphan planets.”
The planet was identified from its faint and unique heat signature by the Pan-STARRS 1 telescope located on Haleakala, Maui. Follow-up observations using other telescopes in Hawaii show that it has properties similar to those of gas-giant planets found orbiting around young stars. The paper describing the discovery is to be published in the journal Astrophysical Journal Letters.
During the past decade, extrasolar planets have been discovered at an incredible pace, with about a thousand found by indirect methods such as wobbling or dimming of their host stars induced by the planet. However, only a handful of planets have been directly imaged, all of which are around young stars (less than 200 million years old). PSO J318.5-22 is one of the lowest-mass free-floating objects known, perhaps the very lowest. But it’s most unique aspect is its similar mass, color, and energy output to directly imaged planets.
“Planets found by direct imaging are incredibly hard to study, since they are right next to their much brighter host stars. PSO J318.5-22 is not orbiting a star so it will be much easier for us to study. It is going to provide a wonderful view into the inner workings of gas-giant planets like Jupiter shortly after their birth,” said Dr Niall Deacon of the Max Planck Institute for Astronomy in Germany and a co-author of the study, according to a university statement.
PSO J318.5-22 was discovered during a search for the failed stars known as brown dwarfs. Due to their relatively cool temperatures, brown dwarfs are very faint and have very red colors. To circumvent these difficulties, Liu and his colleagues have been mining the data from the PS1 telescope. PS1 is scanning the sky every night with a camera sensitive enough to detect the faint heat signatures of brown dwarfs. PSO J318.5-22 stood out as an oddball, redder than even the reddest known brown dwarfs.
“We often describe looking for rare celestial objects as akin to searching for a needle in a haystack. So we decided to search the biggest haystack that exists in astronomy, the dataset from PS1,” said Dr Eugene Magnier of the Institute for Astronomy at the University of Hawaii at Manoa and a co-author of the study, according to a University statement. Dr Magnier leads the data processing team for PS1, which produces the equivalent of 60,000 iPhone photos every night. The total dataset to date is about 4,000 Terabytes, bigger than the sum of the digital version of all the movies ever made, all books ever published, and all the music albums ever released.